Process for the conversion of hydrocarbon fractions containing condensed-ring polycyclic aromatic hydrocarbon

ABSTRACT

Process for the catalytic hydrogenative ring opening of hydrocarbon fractions containing condensed ring polycyclic hydrocarbons in the presence of a new catalyst comprising a carrier of NaY-type zeolite, at least 60% (mol) of the sodium ions contained in said zeolite having been exchanged with nickel ion, supported thereon nickel, tungsten and vanadium. The new catalyst exhibits an excellent hydrogenative ring opening activity.

United States Patent Abiko et al.

PROCESS FOR THE CONVERSION OF HYDROCARBON FRACTIONS CONTAINING CONDENSED-RING POLYCYCLIC AROMATIC HYDROCARBON Inventors: Shiro Abiko; Kazuo Yorihiro, both of Yokkaichi; Toshiyuki Sugihara; Masakazu Hanawa, both of Ami, all of Japan Mitsubishi Co., Petrochemical Ltd., Japan Filed: Mar. 12, 1974 Appl. No.: 450,395

Assignee:

Foreign Application Priority Data Mar. 15, 1973 Japan 48-30205 US. Cl 208/111; 208/73; 252/455 Z; 252/456; 252/464 Int. Cl. ..Cl0G 13/06; C10G 37/02; B011 29/12- Field of Search 208/111, 72, 73, 58, 61; 252/455 Z, 456

References Cited UNITED STATES PATENTS 5/1964 Kelley et al 208/60 Primary ExaminerDelbert E. Gantz Assistant ExaminerG. E. Schmitkons Attorney, Agent, or Firm-Robert E. Burns; Emmanuel J. Lobato; Bruce L. Adams [57] ABSTRACT Process for the catalytic hydrogenative ring opening of hydrocarbon fractions containing condensed ring polycyclic hydrocarbons in the presence of a new catalyst comprising a carrier of NaY-type zeolite, at least 60% (mol) of the sodium ions contained in said zeolite having been exchanged with nickel ion, supported thereon nickel, tungsten and vanadium. The new catalyst exhibits an excellent hydrogenative ring opening activity.

1 9 Claims, No Drawings PROCESS FOR THE CONVERSION OF HYDROCARBON FRACTIONS CONTAINING CONDENSED-RING POLYCYCLIC AROMATIC HYDROCARBON BACKGROUND OF THE INVENTION 1. Field of The Art The present invention relates to a process for the hydrogenative ring opening of polycyclic hydrocar-' bons. In particular, it is concerned with a process for the hydrogenative ring opening of polycyclic hydrocarbons or heavy hydrocarbon oils containing a large amount of polycyclic hydrocarbons which comprises contacting these hydrocarbon materials with a novel catalyst having a high activity under highly pressurized hydrogen.

Such type of catalyst have, heretofore, been used in hydrocracking by which gasoline with a high octane rating is to be produced. The hydrocracking process comprises subjecting heavy oils, particularly gas oil fractions to cracking under pressurized hydrogen, and the principal reactions involved therein are chain cleavage and isomerization of paraffins and hydrogenation and subsequent ring opening of aromatics contained therein. (See, for example, A. Voohries at al: Advances in Petroleum Chemistry and Refining Vol. VIII pp. 169. lnterscience Publishers, New York 1964.) Such reactions may be useful as a pre-treatment means in, for example, thermal-cracking of heavy oils by which raw materials for chemicals are to be produced. For instance, it is known that when the heavy oils are 5 cracking commercially available do not necessarily thermally cracked, the aromatic hydrocarbons contained therein undergo no ring opening under a cracking temperature lower than 900C and, is even dehydrocondensed to form biphenyl type compounds which are retained in the heavy residue oils, so that fuel oils are largely produced and useful light olefins or monocyclic aromatics are not obtained. It is also known that partially hydrogenated condensed ring aromatic hydro carbons are, for the most part, converted tooriginal aromatic hydrocarbons (in this case naphthalene) through a dehydrogenation reaction when they are subjected to heat treatment, (for example, with tetralin, see L. Alexander et al: J. Chem. Soc, B9 1733-9 (70). This fact indicates that hydrogenative ring opening is essential for the pre-treatment of heavy oil for thermal cracking or conversion of heavy oils into light oil.

2. Prior Art In the conventional studies to produce light fractions of hydrocarbons using catalyst for hydrocracking, most of the hydrocarbons used are paraffin hydrocarbons. The conversion of aromatic hydrocarbons are only disclosed in V. C. Rumohr et al: Erdoel und Kohle Erdgas Petrochemie 25 309 (1 972) and paring reaction is disclosed in Sullivan: J. Am; Chem. Soc. 83, 1 156 (1956). The former is directed to the production of a large amount of naphthalene fractions from anthracene, phenanthrene, and the latter is concerned with the cleavage of the side chains of polyalkylbenzene. Studies concerning the hydrogenative ring opening of polycyclic aromatics have been little known.

Although some patents disclose catalysts for the conversion of hydrocarbons which contain the same components as those of the'catalyst of the present invention as hereinafter detailed, these catalysts have been used for the production of high octane gasoline and they are produce excellent results in the tests for such ring opening performance. On the other hand, several patents teach catalyst compositions for hydrocracking containing vanadium as a component, but there are disclosed only a few catalysts having excellent cracking activity wherein zeolite is used as a solid acid carrier. None of these patents gave detailed description of the catalyst containing the zeolite carrier (for example, see US. Pat. Nos. 2,817,626; 2,839,450; 3,383,306; 3,437,586 and 3,640,819 and Japanese Pat. Publication No. 35613/71).

SUMMARY OF THE INVENTION The present invention relates to a process for the production of monocyclic aromatics and alkyl naphthenes with a high yield from hydrocarbons containing a large amount of fused-ring aromatics and the desulfurization of said hydrocarbon fractions in the production of monocyclic aromatic and alkyl naphthenes by effecting the hydrogenative ring opening under pres surized hydrogen in the presence of a catalyst with hydrocracking metals Ni, W and V supported on a carrier of zeolite Y with nickel ion exchanged therewith.

Accordingly, the process for the conversion of hydrocarbon fractions containing polycyclic aromatic hydrocarbon is characterized in that the catalyst hydrogenative ring opening of hydrocarbon fractions containing at least 10% (by weight) polycyclic aromatic hydrocarbons is carried out in the presence of a catalyst comprising a carrier of Y-type zeolite, at least 60% (mol) of the sodium ions contained in said zeolite having'bee'n exchanged with nickel ion, supported thereon l to 25% nickel, 1 to 20% tungsten and 0.1 to 5% vanadium based on the weight of the carrier these metals.

In view of the above, the distinctive characteristics of the present invention are that the zeolite Y which has undergone exchange with nickel ion is used as a carrier and vanadium (and nickel and tungsten) is contained as a catalyst metal component, and for such characteristic, the catalyst of the present invention results in a great improvement in hydrogenative ring opening activity (see the comparative Examples as hereinafter described).

DETAILED EXPLANATION OF THE INVENTION 1. Catalyst 1. Kind of Catalyst (See, D. W. Breck: Molecular Sieve Zeolites, Advances in chemistry Series 101, Am. chem. Soc. Washington D.C.(l97l)).

The catalyst used in the present invention is required to have nickel which substitutes for sodium ions in' a zeolite carrier and also nickel supported on the carrier.

3 v The catalyst according to the present invention may be used in a sulfided form, and it. is usually sulfided in practice.

I 2. Preparation of Catalyst Preparing of Carrier i. A predetermined amount of dry zeolite Y is subjected to ion exchange treatment in a solution of NH.,Cl.-The NH Cl solution used is such that NH, ions are present in an amount of 0.5 to 3 times that of sodium ions contained in the zeolite. The zeolite Y in the form of powder or pellet is immersed in the afore-mentioned solution and heated to a temperature of 80 to 90C and left with stirring for l to 6 hours. At the end of that time, the'resulting mixture is filtered and thoroughly washed with pure water or the solvent.

The ion exchange operation as stated above is repeated 3 to 6 times using a fresh NH Cl solution at every operation, whereby 90 to 95% of the Na ions contained in the zeolite is replaced by NH, ions. The zeolite Y thus exchanged is called NHJY.

, A, predetermined amount of dry zeolite y is subjec't'ed, to ion-exchange treatment in an aqueous solution of salts of nickel. Any kind of salts of nickel which are water-soluble may be used. Nickel nitrate, nickel chloride and the like are usually used. The content of the Ni ions contained in the aqueous solution of nickel salts is usually in the range of from 0.5 to 3.0 timesthat of Na ions..With less amounts of Ni ions, the degree of ion exchange is decreased, so that the number of exchanging operations should be increased. The ion ex H change is carried outaccording to the same procedure described'in (i). The repeated ion exchange over 3. to 6 times could replace 75 to 80% of the sodium ions contained in the zeolite with Ni ions. As is seen in Examples as-hereinafter described, at least 60% of the sodium ions should be replaced with Ni ions.'The zeolite Y-th'us. replaced with Ni ions is called Ni-Y.

iii. The NH Y ion exchanged according to the procedure described in i. is ion exchanged with Ni ions using the same ion exchange method as that described in (ii). The resultant zeolite is called Ni-Nl-h-Y.

Support Of Metal ComponentAnd Sulfiding The afore-mentioned NH Y, Ni--Y or Ni-NH- Y as a used carrier is impregnated with the compounds which are sources of metal components in the form of, preferably, a solution (particularly, an aqueous solution), respectively. Nickel, tungsten and vanadium are deposited on the carrier in the weight ratio of l to 25:1 to 20:0.[ to 5, and, preferably, 6 to 20 1 to 10 l to 2, respectively, calculated on the basis of the assumption that the total of the carrier and the metals amounts to 100.

As a source of nickel, any compounds, preferably, water soluble compounds such as nickel nitrate, which forms metallic nickel on thermal decomposition, may,

be used. The nickel nitrate may be used in the form of a slurry. t

' As a source of tungsten, any compounds, preferably, water-soluble compounds such as ammonium silicotungstate or paratungstate, which form metallic tungsten or tungsten oxides upon thermal decomposition, may be used. As a source of vanadium, any compounds, preferably water-soluble compounds such as ammonium metovanadate, which form metallic vanadium or vanadium oxides may be used.

These compounds may be used as the sourcesof the metal components of the catalyst in any type of combination without havingappreciable effect on the catalytic performance.

The supporting of the metal components on the carrier is carried out by mixing an "aqueous solution or slurry of the respective salts of Ni, W and V with the ion exchanged zeolite Y as stated above and evaporating the resulting mixture to dryness. The mixing may be carried out by treating the mixture'in a kneader for 0.5 to 5 hours.

The mixture is then dried in a dryer at a temperature in the order of to 150C; Thereafter, the dried mixture is calcined in an atmosphere of air or an inert gas such as nitrogen, helium, argon and the like in a muffle furnace. In this case, in order to prevent the occurrence of local high temperatures due to the decomposition of the salts, thecontent is gradually heated from room temperature to a temperature of 200 to 400C and kept at that temperature for 0.5 to 3 hours, after which it is heated at a temperature of 480 to 550C for a further 3 hours.

Following this, the mixture is reduced in a stream of hydrogen at.a temperature of about 350 to 450C for about 0.1 to 5 hours and then pre-sulfided in a stream of hydrogen containing 1 to 15% (by'volume) H 8, CS thiophene and the like.,This sulfiding is carried out in a stream of hydrogen containing H 8, CS thiophene and the like at a temperature of about 200 to 400C for about 1 to 60 minutes. After the sulfiding,the catalyst is cooled to room temperature in an atmosphere of nitrogen. Further, the sulfiding of the catalyst may also be effected by adding a simple organosulfur compound such as thiophene or carbon disulfide at the starting of operation in the hydrocarbon conversion process.

The catalyst thus obtained may be shaped into a tablet and other shaped products, if desired. The shaping may be carried out before the impregnation of the compounds of the catalytic metal component sources, but it is, preferably, carried out after the impregnation, and more preferably after the calcining. The shaping may be carried out using a suitable binder such as silica-alumina, if desired.

upon thermal decomposition,

' 2. Conversion of Hydrocarbon 1. Reaction Conditions:

The reaction conditions of the hydrogenative ring opening of condensed ring aromatic are as follows:

i. Reaction temperature The temperature at which the reaction is carried out may preferably be any temperature within the range of 250 to 500C, and more preferably 350 to 470C. With higher temperatures gasification is increased, while with lower temperatures conversion is decreased. The optimum temperature may be determined depending upon the feed of charge stocks used.

ii. Reaction pressure:

The pressure of hydrogen at which the reaction is conducted may be any pressure in the range of 10 to 200 kg/cm, and preferably, 50 to 150 kg/cm. The higher the pressure the higher the conversion, but at pressures above .100 kg/cm the increase in theconversion slopes down; Therefore, the use of a pressure of from 60 to kg/cm is more preferably in usual operations.

iii. Flow rate of hydrogen:

The higher the flow rate of hydrogen the greater the conversion, but the flow rate usually used in the range of 500 to 5,000 [Hydrogen gas volume/feed liquid volume] with respect to the flow rate of the charge stock. The preferred flow rate ranges from 800 to 1,500 [gas volume/liquid volume].

iv. LHSV (liquid hourly space velocity) The LHSV employed in the process is usually in the range of 0.5 to 6/hr, and preferably 1 to 4/hr.

2. Hydrocarbon Charge Stock The hydrocarbon charge stock used in the present invention is hydrocarbon fractions containing not less than (by weight) and preferably (by weight) of condensed ring aromatic hydrocarbons.

The term condensed ring aromatic hydrocarbons as herein used signifies hydrocarbons which contain at least one benzene ring in the structure of the condensed ring and have, preferably, not less than 10 carbon atoms. Illustrative examples of such condensed ring aromatic hydrocarbon include naphthalene, methylnaptthalenes, anthracene, phenanthrene, pyrene, acenaphthene, tetralin and the like and alkylderivatives thereof.

The hydrocarbon fractions containing not less than 10% of condensed ring aromatic hydrocarbons include FCC recycle oil, vacuum gas oil, straight run heavy gas oil, residue of thermal cracking, coal tar gas oil and the like.

The content of the condensed ring aromatic hydrocarbons present in these hydrocarbon fractions is represented by the weight ratio of aromatic ring forming carbon which is determined from the intensity ratio of aromatic ring constituting hydrogen to other hydrogen by means of a nuclear magnetic resonance (NMR) method.

3. Reaction Result The hydrogenative ring opening of heavy oils containing a large amount of condensed ring aromatics through the use of the aforementioned catalysts enables obtaining of monocyclic aromatics and naphthenes with a high yield.

More specifically, when a-methylnaphthalene as a model of the condensed ring aromatics is, for example, subjected to hydrogenative ring opening to give monocyclic aromatics and naphthenes, the yield of the monocyclic products is 20% (by weight) with the commercially available catalysts NiW/SiO .Al O suitable for hydrocracking while with the NiWV/NiY catalyst of the present invention the monocyclic products can be obtained with a yield of 80% (by weight). The reaction conditions under which the comparative experiments were conducted included a temperature of 450C, a pressure of 80 kg/cm and a LHSV of 2 hr, and the comparative data were mainly taken 2 hours after the a-methylnaphthalene was passed over the catalysts.

4 Experimental Examples EXAMPLE-1 (Catalyst preparation) Catalyst preparation procedure (1) In this procedure, the catalyst is prepared by using an indirect nickel exchange method which will be given hereunder.

500 g of dry zeolite Y was immersed in 21 of an aqueous solution of 107 g NH Cl in water and then, the zeolite was ion exchange treated with stirring while maintaining the mixture at a temperature of to C. After 3 hours, the resulting mixture was filtered and the resulting exchanged zeolite was washed with water, after which the washed zeolite was again subjected to ion exchange treatment in a fresh NH Cl aqueous solution of the same concentration in the same manner described above. When such ion exchange treatment was repeated 3 times, 73% of Na ions was replaced by NH ions. The product thus obtained is called NH -Y (1).

The NH Y(l) was baked in a muffle furnace at 500C for 1 hour, and then shaped into a pellet having a size of 5 mmqS by means of a pelletizing machine.

After shaping, to 30g of NH Y( l) was added 200cc of an aqueous solution of 37.4 g of nickel nitrate (6 hydrate) and 106g of ammonium paratungstate. The resulting mixture was evaporated to dryness to impregnate the NH;,Y (1) with the solution, and the impregnated NH Y (l) was dried in a dryer at a temperature of 110C for 24 hours. After drying, the dried product was calcined at 550C for 3 hours. The catalyst so produced is called Ni W/NH -Y( l On the other hand, 30 g of NH Y( 1) after being shaped was impregnated with an aqueous solution containing 37.4 g of nickel-nitrate (6 hydrate), 1.06g of ammonium paratungstate and 0.386 g of ammonium vanadate and calcined according to the same manner as that described above. The catalyst so produced is called NiWV/NH Y(2).

Catalyst preparation procedure (2) In this procedure, the catalyst is prepared by using a direct nickel exchange method which will be given hereunder.

500 g of dry zeolite is added to a nickel salt aqueous solution of 300 g Ni (NO .6H O in 21 of pure water to form a slurry. The slurry was ion exchange treated with stirring while maintaining it at a temperature of 80 to 90C. After 3 hours, the resulting product was filtered and the resulting exchanged zeolite was washed with water and dried. The dried zeolite was again mixed with a fresh Ni(NO aqueous solution having the same concentration as that of the first solution, and the resulting mixture was left, water washed and filtered and the resulting exchanged zeolite was dried in the same manner as that described above.

Such ion exchange treatment was repeated three times. The drying was carried out in a drier at l 10C for 24 hours. The ion-exchange treatment resulted in the replacement of 75 to 77.5% Na ions with Ni ions. The Ni-exchanged zeolite Y so produced is called Ni- Y( 3).

To 15 g of NiY(3) was added ml of an aqueous solution containing 6.64 g of nickel nitrate hexahydrate, 0.5297g of silicotungstic acid and 0.1926 g of ammonium metavandate and the resulting mixture was evaporated to dryness to attain the impregnation of Ni, W, and V components. After the impregnated Ni- -Y(3) was dried at a temperature of 110C for 24 hours, the dried Ni-Y(3) was introduced into a muffle furnace and first calcined ata temperature of 300C for 1 hour, after which the temperature was gradually raised to 500C and calcining was further carried out at that temperature for 3 hours. After the grinding of the calcined grains, the ground productwas shaped into pellets having a size of mm by means of a pelletizing machine. The pellets were baked at a temperature of 500C for 1 hour. The catalyst so obtained is called NiWV/NiY(3).

Chemical analysis showed that the NiWV/Ni- Y(3) catalyst contained 2.2 weight percent sodium,

As can be seen from Table l, the comparison of the catalyst NiW/Nl-l Y(l) with the catalyst Ni- WV/Nl-l Y(2), both catalysts being prepared according to the catalyst preparation procedure (1), indi- 5 cates that the addition of vanadium results in a substantial improvement in hydrogenative ring opening activity.

EXAMPLE-3 10 (Hydrocarbon conversion) was passed over the catalyst are shown in Table 2.

16.2 weight percent nickel (including Ni in the carrier NiY), 1.6 weight percent tungsten and 1.6 weight percent vanadium, calculated on the basis of the cata- As is apparent from Table 2, the absence of W or V affects conversion very little, but causes reduction in ring opening activity. The other conversion products lyst dried at 200C for 2 hours (since approximately 77 include predominantly indane, tetralin and methyl demolar of sodium ion was exchanged with nickel ion in the carrier NiY(3), the amount of impregnated nickel is 10.5% by weight.)

EXAMPLE-2 rivatives thereof which are undesirable forthe purpose of the present invention.

EXAMPLE-4 (Hydrocarbon conversion) Using the catalysts of Example 1 wherein the degree (Hydrocarbon conversion) l-lydrogenative ring opening reaction was performed using (wt-methylnaphthalene (which was selected as a model of the condensed ring aromatics) as a hydrocarof ionexchange of the NiY carrier was varied as indicated in Table 3, hydrogenative ring opening reaction was performed according to the same procedure de-.

scribed in Example 2 and the comparison of catalysts bon oil change. Prior to the reaction, all the catalysts performance was carried out 2 hours after the charge were reduced in a stream of hydrogen at a temperature of 400C for 3 hours, and then cooled in a stream of nitrogen to 300C and sulfided in a stream of a mixture of 10% (by volume) of H 8 and 90 (by volume) of stock was passed over the catalysts.

The results are shown in Table 3. The higher the ionexchange the better the hydrogenative ring opening activity, and it is clear that the degree of ionexchange hydrogen: of not less than 60 is required.

The efficiency of the catalysts was compared at undergiven reaction conditions a temperature of 450C, a pressure of 80 kglcm a LHSV of 2 hr, a catalyst amount of 15cc and H /oil 1,000 Nm /K1. The com- Table 3 Yield of ring opened parative data were obtained 10 hours after the a- 40 47 methylnaphthalene was passed .over the catalysts. 71 The results are shown in Table 1. In this connection, 33 g; the yields of monocyclic aromatics and decalin are represented by weight percent based on the weight of Experimental conditionsl g y t g -g empera ure the charge stock. 55 Pressure mks/cm,

Table 1 Percent Percent conversion of yield of Catalyst a-methylnaphthalene monocyclic aromatics and decalin Comparative Example Ni-W/NH,-Y(1 66 47 Present Invention Ni-W-V/NH,Y(2) 82 70 Comparative Ni-W/SiO,.Al,O S2 17 23 Example Ni-W-V/SiO,.Al O

EXAMPLE in this example, hydrogenative ring opening reaction was carried out using various catalysts prepared according to different preparation procedures.

The reaction conditions were identical to those described in Example 2, and the data were obtained hours after the charge stock was passed over the catalysts.

COMPARATIVE EXAMPLE 2 Table 4 Percent Style of Percent yield of monocatalyst preparation procedure conversion of cyclic aromatics a-methylnaphthalene and decalin 1 Exchange, 2 lmpregnation, 3 Shaping* 82 72 l Shaping, 2 Exchange, 3 lmpregnation** 76 65 1 Exchange, 2 Shaping, 3 lmpre'gnation* 85 67 'Ni-N-V/Ni-Y prepared by the catalyst preparation procedure (2) "Ni-W-V/Ni-Y prepared by altering the order of shaping.

As is clear from Table 4, the procedure according to Table 6 catalyst preparation procedure (2) described above, Percent namely, the procedure of 1 Exchange, 2 lmpregna- Catalyst yield f monocyclic tion, 3 Shaping is most preferable... aroma'lcs and decalm Ni-W/NH,,-Y* 50** Ni-W/Nl-Y* 70.5**

COMPARATIVE EXAMPLE 1 In this example, hydrogenative ring opening reaction was carried out using NiW'-'-V/MY catalysts in which M-Y was varied as indicated inTable 5. Ni-Y was found to be the most useful carrier.

The catalyst preparation procedure and the hydrocarbon conversion process were similar to the catalyst preparation procedure (2) and Example 2, respectively. The conditions of .the hydrocarbon conversion process were as follows: Temperature: 450C, pressure: 80 kg/cm, LHSV: 2 hr". The data were obtained 1.5 hours after the charge stock was'passed over the catalysts. The results are shown in Table 5.

Table 5 EXAMPLE 6v Using various hydrocarbon fractions as the charge stocks, hydrogenative ring opening reaction was performed in the presence of the catalyst of the present invention and the catalyst commercially available, respectively.

The catalyst (NiWV/Ni-Y) of the'present invention which was prepared according to the same procedure as the catalyst preparation procedure (2) as stated above contained 2.2 weight percent sodium, l6.2 weight percent nickel, 1.6 weight percent tungsten and 1.6 weight percent vanadium.

The commercial catalyst consisted of Ni-W/SiO Metal ion used Yield of rin opened .Al O for use in hydrogenative ring opening and conexchange Exchange pmdum ('nclu mg decal'n) tained 6.5 weight percent nickel and 20.0 weight per- Ni 75 83 cent tungsten, calculated as the respective metal ox- Ca 87 44 ides Al 52 I M 71 50 The treatment conditions are shown in Tables 7, 8 73 63 and 9. Further, the range of the boiling point of the change stock was determined according to AST- M-D-86-66, and the t e of the h drocarbon was yP y analyzed according to ASTM-D-2425-T.

Table 7 Run No. l 2 3 4 Treatment condition 7 Temperature (C) 380 400 Pressure (kg/cm Charge oil Charge oil LHSW (hr") Catalytically 2 Heavy oil 2 H /charge oil (Nm lKL) cracked light 800 from thermal 800 oil cracking Catalyst Present Commercial Present Commercial invention catalyst invention catalyst Properties and analysis Boiling range IBP(C) 217 52 75 98 50% (C) 265 235 249 294 220 235 Run No.

lndane, tetraline, etc.)

n zn-to Blcycllc aromatics 26.2 (Naphthalene CIIHZIH n 2 1-1: Trlcycllc aromatlcs 0.8

'Liquid-Hourly-Space-Vclo1:ity

Run No.

Treatment condition Temperature (C) Pressure (kglc'm G) H lcharge oil (Nm"/KL) (THGO Catalyst v Properties and anal sis Boilingrange 181 (C) 242 V V 50 ("C) 307 FBP ('C) 364 Specific gravity (IS/4C) 0.852

Refractive Index (n,,') 1.4750

Total ,sulfur weight% 1 .22 Molecular weight 245 T of'h drocarbon y y (mass sEctrometry) gweight ara 1n 50.5

Naphthene 23.7

Monocyclic paraffin -Dicycloparaffin Tricyclicparaffin Monoc clic aromatics 13.2

Alky benzene lndan tetralin, etc.

n III III Bicyclic aromat1cs 10.6 (Naphthalenes 11 1 1-10 Trlcycllc aromatlcs I 2.0

Table 9 Run No: Treatment condition Temperature (PC) Char e oil Pressure kg/cm'G) Ll-lSV (hr H,/charge oil (Nm 'lKL) 011 Catalyst .Pro rties and analysis Specific gravity (IS/4C) l Refractive lndex (n,,) 3 8 Total sulfufl" (weight 9 Paraffin Monocyclic aromatics 29.7

n In 10 B|cyc11c aromatics 60.5

Table 7-continued Table 8 Charge oil Heavy gas oil Present 7 Commercialwou- As halt cracked I 100 dist1 late light Present Invention Alkyl benzene 20.4 26. lndan, tetra1in, etc. 1%.

Char s oil 1 100 lawn Present Commercial Table 9-continued Run No. 15 Treatment condition Naphthalene 33.0 25.7 C l-l 14.9 11.8 n 12.6 11.4

Tricyclic aromatics 9 g 6.7

Distillation test 1 BP 230C 118C 264 241 50 285 275 70 306.5 295 EP 350 (91 354 (97.7)

According to MCTS method REFERENCE EXAMPLE Several products resulting from the hydrogenative ring opening reaction of Example 6 were subjected to tubular furnace steam thermal cracking in a tube. The results of the mass balance are shown in Table 10.

Table 10 What we claim is:

l. A process for conversion of a hydrocarbon fraction containing at least 10 by weight of condensedring polycyclic aromatic hydrocarbons which comprises hydrogenative ring opening and hydrocracking of said polycyclic aromatic hydrocarbons by hydrogen into substantially monocyclic aromatics and saturated cyclic hydrocarbons in the presence of a catalyst comprising 1 to 25% of nickel, 1 to 20% of tungsten and 0.1 to 5% of vanadium, based on the total weight of a carrier plus the three metals supported on said carrier, which carrier consists of an NaY zeolite in which more than molar of sodium ions have been exchanged with nickel ions.

2. A process according to claim 1 wherein said catalyst comprises 6' to 20% of nickel, 1 to 10% of tungsten and l to 2% of vanadium, based on the total weight of the carrier plus the three metals.

3. The process according to claim 1 wherein he catalyst is sulfided prior to the hydrogenative ring opening reaction.

4. The process according to claim 3 wherein the sulfiding is effected by heating the catalyst in an atmosphere comprising-hydrogen and vapor of a sulfide.

5. The process according to claim 1 wherein the exchange of sodium ions of the zeolite Y is effected by exchanging the sodium ions with ammonium ions in an aqueous solution and then exchanging the ammonium ions with nickel ions in an aqueous solution.

6. The process according to claim 5 wherein the ammonium ions are provided by a water soluble ammonium salt which yields ammonium ions in an aqueous solution.

7. The process according to claim 6 wherein the ammonium salt is ammonium chloride.

8. The process according to claim 5 wherein the nickel ions are provided by a water-soluble nickel salt which yields nickelions in an aqueous solution.

9. The process according to claim 8 wherein the nickel salt is selected from the group of nickel chloride and nickel nitrate. 

1. A PROCESS FOR CONVERSION OF A HYDROCARBON FRACTION CONTAINING AT LEAST 10 % BY WEIGHT OF CONDENSED-RING POLYCYCLIC AROMATIC HYDROCARBONS WHICH COMPRISES HYDROGENATIVE RING OPENING AND HYDROCRACKING OF SAID POLYCYCLIC AROMATIC HYDROCARBONS BY HYDROGEN INTO SUBSTANTIALLY MONOCYCLIC AROMATICS AND SATURATED CYCLIC HYDROCARBONS IN THE PRESENCE OF A CATALYST COMPRISING 1 TO 25% OF NICKEL, 1 TO 20% OF TUNGSTEN AND 0.1 TO 5% OF VANADIUM, BASED ON THE TOTAL WEIGHT OF A CARRIER PLUS THE THREE METALS SUPPORTED ON SAID CARRIER, WHICH CARRIER CONSISTS OF AN NAY ZEOLITE IN WHICH MORE THAN 60 MOLAR % OF SODIUM IONS HAVING BEEN EXCHANGED WITH NICKEL IONS.
 2. A process according to claim 1 wherein said catalyst comprises 6 to 20% of nickel, 1 to 10% of tungsten and 1 to 2% of vanadium, based on the total weight of the carrier plus the three metals.
 3. The process according to claim 1 wherein he catalyst is sulfided prior to the hydrogenative ring opening reaction.
 4. The process according to claim 3 wherein the sulfiding is effected by heating the catalyst in an atmosphere comprising hydrogen and vapor of a sulfide.
 5. The process according to claim 1 wherein the exchange of sodiUm ions of the zeolite Y is effected by exchanging the sodium ions with ammonium ions in an aqueous solution and then exchanging the ammonium ions with nickel ions in an aqueous solution.
 6. The process according to claim 5 wherein the ammonium ions are provided by a water soluble ammonium salt which yields ammonium ions in an aqueous solution.
 7. The process according to claim 6 wherein the ammonium salt is ammonium chloride.
 8. The process according to claim 5 wherein the nickel ions are provided by a water-soluble nickel salt which yields nickel ions in an aqueous solution.
 9. The process according to claim 8 wherein the nickel salt is selected from the group of nickel chloride and nickel nitrate. 